The present invention relates to an information processing system, and more particularly to a configuration management system for the software of equipment. Here in this specification, the expression "configuration management" signifies to manage information based on the connectional relations, working status and operating environments of the constituents of a network system such as various computers, printers and circuits.
It is extensively practiced that a plurality of machines are connected through a network so as to permit one machine to utilize the resource of another machine. In a system thus constructed, the machine which offers the resource is called a "server" (or "server equipment"), while the machine which utilizes the resource is called a "client" (or "client equipment"). Heretofore, in the client/server system, a program called "redirector" has been located on the client side, and the requests of the client for accesses to the network have been processed by classifying the access requests into local and network requests by means of the redirector. Since the redirector is the program required for accessing the server, it cannot be located in the server, and this is the main reason for it being located in the client.
With the conventional technique, when updating the redirector, an update procedure needs to be executed in each individual client. This has led to the problem that much labor is expended in updating redirectors in a network system which has a large number of clients. Moreover, since the redirectors are manually updated, some of the redirectors are liable to not be updated. This has caused inconsistency of the whole system attributed to redirectors of different versions existing within the system. Especially in the presence of different types of clients, it has not been considered to update the redirectors in accordance with the types.
Meanwhile, the client is a machine which can also be used in a stand alone mode, and it can utilize both the resources of local resources peculiar to the particular client and remote resources including the server. Here, the expression "remote resources" is a general name to describe various resources such as the server, a shared disk storage and a shared printer, and the server is one of the remote resources.
In this regard, resource names which are used when each client utilizes the remote resources have been defined in the local resource of the client. Since the resource names are information required before connecting the client to the server etc., they need to be located in the client. When the remote resource management information differs for every client, the user of the system who has changed the client to-be-used might find themselves in the situation where, since a server resource name for accessing the server, for example, is different, a program used before is not operated without any modification. In order to avoid this drawback, an information server which unitarily manages the remote resource management information items of the respective clients is provided, and the clients obtain the remote resource management information items from the information server. In this way, under the mere condition that the clients store the resource name of the information server therein, the information items on the other remote resources can be managed in a unified fashion by the system.
With the above conventional technique, the remote resource management information items to be used by the clients are located in the information server and are accessed through the network.
On the other hand, however, local resource management information items which are required before the machines become accessible to the network, for example, when the power sources of the clients are turned ON, are not managed in the conventional system.
As another problem, since such local management information items are updated in the individual clients independently of one another, it has been very difficult to ascertain the history of the local management information items of all the clients.
The purpose of managing the history is, for example, to rectify the cause in the event of a fault. This operation is necessitated for a presumed situation as stated below.
In a case where a shared resource (for example, shared printer or shared modem) to which only one client is accessible at one time is to be used in the network system, the client needs to perform the so-called exclusion control of checking if any other client is using the shared resource and then bringing the shared resource into an "occupied" status if no other client is using this resource, before commencing use, and bringing the shared resource back into an "unoccupied" status after use.
Herein, when a certain client is to use the shared resource, it ought to run an AP (application program) which properly performs the exclusion control. Nevertheless, the user of the client is assumed not to hold such an AP and therefore to have unconditionally made the modification that the shared resource shall be brought into the "occupied" status at the start of the pertinent client's use of the resource irrespective of the actual status thereof, at their discretion without notifying the modification of the status to the manager of the system. Then, there arises the problem that, whereas the client having made the improper modification can utilize the shared resource, any other client properly performing the exclusion control cannot utilize the shared resource at all because of the continuous "occupied" status.
In such a case, since no trouble is indicated in the client actually causing the problem, the manager does not try to inspect the pertinent client. In any case, even when the manager inspects the malfunctioning client, they can never find the cause.
On this occasion, when the history of the modifications of the local resources of all the clients is stored, the modification of the configuration of the pertinent client can be confirmed to have been at the line of the malfunction of the other client, which greatly facilitates clearing up the cause of the malfunction.